Neurotransmitters

Neurotransmitters are signaling molecules important for propagation of a neuronal signal. Neurons synthesize and/or import neurotransmitters, and package them into presynaptic vesicles. Vesicles released by presynaptic neurons propagate a neuronal impulse. Each type of neurotransmitter has a specific cognate receptor family (e.g., dopamine), although some neuropeptides are co-released with a primary neurotransmitter and interact with the same receptor family (e.g., dopamine and neurotensin). Neurotransmitter receptors act through diverse G-protein coupled and G-protein independent mechanisms that trigger downstream intracellular signal cascades including the cAMP/PKA, PI3K/AKT, phospholipase A2, and phospholipase C pathways. Some neurotransmitter receptors are purely excitatory, such as glutamatergic receptors, whereas others are largely inhibitory, such as γ-aminobutyric acid (GABA) and dopamine receptors. Other receptor classes, such as serotonergic receptors, can be either excitatory or inhibitory. Dopamine affects brain processes that control both motor and emotional behavior, and plays a role in the brain’s reward mechanism. Serotonin is critical in temperature regulation, sensory perception, locomotion, and sleep. Dysregulation of GABAergic or glutamatergic synaptic transmission results in a wide variety of nervous system disorders, including chronic pain, psychiatric diseases, neurodegenerative diseases, and insomnia. Serotonergic and dopaminergic pathway dysfunction can cause a variety of neurological and psychiatric disorders including Parkinson’s disease, schizophrenia, bipolar disorder, depression, and addiction. ...

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Neurotransmitters are signaling molecules important for propagation of a neuronal signal. Neurons synthesize and/or import neurotransmitters, and package them into presynaptic vesicles. Vesicles released by presynaptic neurons propagate a neuronal impulse. Each type of neurotransmitter has a specific cognate receptor family (e.g., dopamine), although some neuropeptides are co-released with a primary neurotransmitter and interact with the same receptor family (e.g., dopamine and neurotensin). Neurotransmitter receptors act through diverse G-protein coupled and G-protein independent mechanisms that trigger downstream intracellular signal cascades including the cAMP/PKA, PI3K/AKT, phospholipase A2, and phospholipase C pathways. Some neurotransmitter receptors are purely excitatory, such as glutamatergic receptors, whereas others are largely inhibitory, such as γ-aminobutyric acid (GABA) and dopamine receptors. Other receptor classes, such as serotonergic receptors, can be either excitatory or inhibitory. Dopamine affects brain processes that control both motor and emotional behavior, and plays a role in the brain’s reward mechanism. Serotonin is critical in temperature regulation, sensory perception, locomotion, and sleep. Dysregulation of GABAergic or glutamatergic synaptic transmission results in a wide variety of nervous system disorders, including chronic pain, psychiatric diseases, neurodegenerative diseases, and insomnia. Serotonergic and dopaminergic pathway dysfunction can cause a variety of neurological and psychiatric disorders including Parkinson’s disease, schizophrenia, bipolar disorder, depression, and addiction.